aphthous,a.Path.|ˈæfθəs|[ad.mod.L. aphthōs-us (Fr.aphtheux),f.aphtha: see -ous.]Of the nature of, or characterized by, aphtha.1757Whytt inPhil.Trans.L. 572Tongue..with a beginning aphthous crust on some parts of it.1830LindleyNat.Syst.Bot.7Aphthous affections of the mouth.1849–52ToddCycl.Anat.IV. 1155/1An aphthous tongue.